Dyne Therapeutics, Inc. 4

John Cox (CEO & President of Dyne Therapeutics, Inc.) automatically sold 4,986 shares of common stock at about $26.28 per share to satisfy tax withholding on RSU vesting.

On August 13, 2026, John Cox, CEO & President of Dyne Therapeutics, Inc., executed an automatic sale of 4,986 shares of Dyne common stock at a weighted average price of approximately $26.28 per share, totaling about $131,000, to cover tax withholding obligations arising from the vesting of previously granted restricted stock units under a pre-established Rule 10b5-1 binding contract, and following this transaction he continued to beneficially own 363,165 shares directly plus additional indirect holdings of 72,000 shares held in four separate trusts for his children, along with 248,314 unvested RSUs.

Filing Facts

CIK

1818794

Ticker

DYN

Form

4

Source Type

fda

Accession

0001498428-26-000004

Alert Tier

5